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61.
Abbas Abbasnia Nader Yousefi Amir Hossein Mahvi Ramin Nabizadeh Majid Radfard Mahmood Yousefi 《人类与生态风险评估》2019,25(4):988-1005
The present study evaluates the groundwater quality for drinking and agricultural purposes and determines physicochemical characteristics of groundwater in the Sistan and Baluchistan province in Iran. In order to investigate the water quality, sampling was done in 654 open dug wells, the chemical parameters were analyzed, and water quality index was determined. In this regard, Langelier saturation index (LSI), Ryznar Stability index (RSI), Puckorius scaling index (PSI), Larson–Skold index (LS), and Aggressiveness index (AI) were considered to determine water suitability for industrial purposes. Finally, the analytical results were taken to generate the numerical spatial distribution of the parameters using the geographic information system (GIS) environment. According to the results, water sources were less corrosive based on AI and PSI, low and light corrosion according to RSI, and corrosion according to the Larsson–Sckold index. The results of the drinking water quality index showed that 1.2% shared extraction wells were classified as excellent, 52.1% as good, 39% as poor, 6% as very poor, and 1.7% as unsuitable for drinking purpose classes. In addition, irrigating water quality index illustrated that 19.9% and 80.1% wells were placed in the “excellent” and “Good” classes, respectively. Also, the quality of water in this study was categorized as brackish. 相似文献
62.
Saeid Khakisahneh Xue-Ying Zhang Zahra Nouri De-Hua Wang 《Microbial biotechnology》2022,15(3):817-831
Endothermic mammals have a high energy cost to maintain a stable and high body temperature (Tb, around 37°C). Thyroid hormones are a major regulator for energy metabolism and Tb. The gut microbiota is involved in modulating host energy metabolism. However, whether the interaction between the gut microbiota and thyroid hormones is involved in metabolic and thermal regulations is unclear. We hypothesized that thyroid hormones via an interaction with gut microbiota orchestrate host thermogenesis and Tb. l -thyroxine-induced hyperthyroid Mongolian gerbils (Meriones unguiculatus) increased resting metabolic rate (RMR) and Tb, whereas Methimazole-induced hypothyroid animals decreased RMR. Both hypothyroid and hyperthyroid animals differed significantly in faecal bacterial community. Hyperthyroidism increased the relative abundance of pathogenic bacteria, such as Helicobacter and Rikenella, and decreased abundance of beneficial bacteria Butyricimonas and Parabacteroides, accompanied by reduced total bile acids and short-chain fatty acids. Furthermore, the hyperthyroid gerbils transplanted with the microbiota from control donors increased type 2 deiodinase (DIO2) expression in the liver and showed a greater rate of decline of both serum T3 and T4 levels and, consequently, a more rapid recovery of normal RMR and Tb. These findings indicate that thyroid hormones regulate thermogenesis depending on gut microbiota and colonization with normal microbiota by caecal microbial transplantation attenuates hyperthyroid-induced thermogenesis. This work reveals the functional consequences of the gut microbiota-thyroid axis in controlling host metabolic physiology and Tb in endotherms. 相似文献
63.
RNA and DNA molecules experience motions on a wide range of time scales, ranging from rapid localized motions to much slower collective motions of entire helical domains. The many functions of RNA in biology very often require this molecule to change its conformation in response to biological signals in the form of small molecules, proteins or other nucleic acids, whereas local motions in DNA may facilitate protein recognition and allow enzymes acting on DNA to access functional groups on the bases that would otherwise be buried in Watson-Crick base pairs. Although these statements make a compelling case to study the sequence dependent dynamics in nucleic acids, there are few residue-specific studies of nucleic acid dynamics. Fortunately, NMR studies of dynamics of nucleic acids and nucleic acids-protein complexes are gaining increased attention. The aim of this review is to provide an update of the recent progress in studies of nucleic acid dynamics by NMR based on the application of solution relaxation techniques. 相似文献
64.
Yousefi R Imani M Ardestani SK Saboury AA Gheibi N Ranjbar B 《Acta biochimica et biophysica Sinica》2007,39(10):795-802
Calprotectin, a heterodimeric complex belonging to the S 100 protein family, has been found predominantly in the cytosolic fraction of neutrophils. In the present study, human calprotectin was purified from neutrophils using two-step ion exchange chromatography. The purified protein was used for circular dichroism study and fluorescence analysis in the presence of calcium and zinc at physiological concentrations, as well as for assessment of its inhibitory activity on the K562 leukemia cell line. The thermal stability of the protein at pH 7.0 (physiological pH) and 8.0 (similar to intestinal pH) was also compared. The results of cell proliferation analysis revealed that human calprotectin initiated growth inhibition of the tumor cells in a dose- dependent manner. The intrinsic fluorescence emission spectra of human calprotectin (50 ktg/ml) in the presence of calcium and zinc ions show a reduction in fluorescence intensity, reflecting a conformational change within the protein with exposure of aromatic residues to the protein surface that is important for the biological function of calprotectin. The far ultraviolet-circular dichroism spectra of human calprotectin in the presence of calcium and zinc ions at physiological concentrations show a decrease in the m-helical content of the protein and an increase in [3- and other structures. Our results also show that increasing the pH level from 7.0 to 8.0 leads to a marked elevation in the thermal stability of human calprotectin, indicating a significant role for pH in the stability of calprotectin in the gut. 相似文献
65.
Elham Safarzadeh Shahryar Hashemzadeh Pascal H.G. Duijf Behzad Mansoori Vahid Khaze Ali Mohammadi Tohid Kazemi Mehdi Yousefi Milad Asadi Hamed Mohammadi Farhad Babaie Behzad Baradaran 《Journal of cellular physiology》2019,234(4):3515-3525
Evading immune destruction is a hallmark of cancer. Myeloid-derived suppressor cells (MDSCs), a heterogeneous population of myeloid immune cells, are thought to foster the establishment of an immunosuppressive tumor microenvironment, but it remains unclear how. This study aims to determine the levels of circulating MDSCs and their subpopulations and test their immunosuppressive functions in patients with breast cancer (BC). We analyzed the fractions of MDSCs in freshly isolated peripheral blood mononuclear cells of patients with BC and healthy donors using flow cytometry. Circulating MDSCs were further phenotyped using fluorescently labeled antihuman monoclonal antibodies. Coculture experiments revealed the effects of MDSCs on CD3+ T cell response. Moreover, we correlated circulating MDSC levels with clinicopathological features of patients with BC. We show that the fraction of HLA-DR – CD33 + MDSCs in peripheral blood is about 10-fold higher in patients with BC than in healthy control individuals. The levels of all MDSC subpopulations, including monocytic and granulocytic MDSCs, are significantly elevated. Coculture experiments of purified HLA-DR – CD33 + MDSCs and CD3 + T cells demonstrate that T cell proliferation is more effectively inhibited by BC patient-derived MDSCs than by healthy control MDSCs. Moreover, increased circulating MDSC levels robustly associate with advanced BC stage and positive lymph node status. By being more abundant and more effective T cell suppressors, BC patient-derived circulating MDSCs exert a dual immunosuppressive effect. Our findings pave the way to develop novel diagnostic and immunotherapeutic strategies, aimed at detecting and inhibiting MDSCs in patients with BC. 相似文献
66.
Aynaz Mihanfar Javad Aghazadeh Attari Iraj Mohebbi Maryam Majidinia Mojtaba Kaviani Mehdi Yousefi Bahman Yousefi 《Journal of cellular physiology》2019,234(4):3238-3253
The cancer stem cell (CSC) model encompasses an advantageous paradigm that in recent decades provides a better elucidation for many important biological aspects of cancer initiation, progression, metastasis, and, more important, development of multidrug resistance (MDR). Such several other hematological malignancies and solid tumors and the identification and isolation of ovarian cancer stem cells (OV-CSCs) show that ovarian cancer also follows this hierarchical model. Gaining a better insight into CSC-mediated resistance holds promise for improving current ovarian cancer therapies and prolonging the survival of recurrent ovarian cancer patients in the future. Therefore, in this review, we will discuss some important mechanisms by which CSCs can escape chemotherapy, and then review the recent and growing body of evidence that supports the contribution of CSCs to MDR in ovarian cancer. 相似文献
67.
Type 1 diabetes, has been recognized as an autoimmune disease. Like other immunological conditions, regulation of immune response is a key strategy to control the autoimmunity in diabetic patients. Mesenchymal stem cells have been shown to have a distinct potential in modulating the immune reactions. However, treatment with stem cells is combined with concerns about safety issues. To overcome these concerns, in this study, we have utilized the regenerative potential of exosomes isolated from menstrual blood-derived mesenchymal stem cells to restore the β-cell mass and insulin production in type 1 diabetes. Exosomes are nanovesicles containing various cargos involved in cellular communications. Streptozotocin was used to induce islet destruction and diabetes in male Wistar rats. Then, exosomes were intravenously injected into animals at different time points and in a single or repeated therapeutic doses. After about 6 weeks, animals were euthanized and the pancreas was analyzed for the presence of the regenerated β islets as well as the insulin secretion. The non-fasting blood glucose and the serum insulin level were also monitored during the study. Our results represented that menstrual blood-derived mesenchymal stem cell-derived exosomes enhance the β-cell mass and insulin production in the pancreas of diabetic animals that received repeated doses of exosomes. Immunohistochemistry analysis also confirmed the presence of insulin in the islets of treated animals. Further investigations proposed that exosomes induce the islet regeneration through pancreatic and duodenal homeobox 1 pathway. The exosome tracking also revealed the homing of injected exosomes to the pancreas. 相似文献
68.
69.
Mohammadreza Yousefi Mina Mamipour Sadiye E. Sokullu Shahrooz Ghaderi Hassan Amini Reza Rahbarghazi 《Journal of cellular physiology》2019,234(11):19451-19463
Cardiac progenitor cells (CPCs) have the potential to differentiate into several cell lineages with the ability to restore in cardiac tissue. Multipotency and self-renewal activity are the crucial characteristics of CPCs. Also, CPCs have promising therapeutic roles in cardiac diseases such as valvular disease, thrombosis, atherosclerosis, congestive heart failure, and cardiac remodeling. Toll-like receptors (TLRs), as the main part of the innate immunity, have a key role in the development and differentiation of immune cells. Some reports are found regarding the effect of TLRs in the maturation of stem cells. This article tried to find the potential role of TLRs in the dynamics of CPCs. By showing possible crosstalk between the TLR signaling pathways and CPCs dynamics, we could achieve a better conception related to TLRs in the regeneration of cardiac tissue. 相似文献
70.
Shima Hadifar Abolfazl Fateh Mohammad Hadi Yousefi Seyed Davar Siadat Farzam Vaziri 《Journal of cellular physiology》2019,234(3):2104-2111
Today, diagnosis, vaccination, and treatment of tuberculosis (TB) remain major clinical challenges. Therefore, an introduction of new diagnostic measures and biomarkers is necessary to improve infection control. The ideal biomarker for TB infection can be defined as a host or pathogen-derived biomolecule, which is potent for identifying infection and determining its clinical stage. Exosomes, defined as cell-derived nanovesicles released into biological fluids, are involved in cell–cell communication and immune modulation. These vesicles have emerged as a new platform for improving the clinical diagnosis and prognosis of different infectious diseases and cancers. The role of these nanovehicles, as alternative biomarkers for the improvement of TB diagnosis and treatment, has been demonstrated in a significant body of literature. In this review, we summarized recent progress in the clinical application of exosome-based biomarkers in TB infection. 相似文献